Recently, devices such as mobile phones, smartphones, personal digital assistants (PDAs), and handheld game consoles are being equipped with motion sensors. Herein, a motion sensor refers to a sensor for detecting the motion of a mobile phone handset 1, and may be an acceleration sensor, a gyro sensor, or a magnetic sensor, for example.
Several technologies using motion sensors have been proposed. For example, a motion sensor may be used as follows in order to detect the movement of infants. An acceleration sensor or similar distance detecting means is attached to each infant being cared for at a nursery or similar facility, and the infants' movements are continuously recorded. The infants are also recorded using a TV camera designed for image processing, or similar position detecting means. The position of each infant is detected without identifying the infants themselves. Subsequently, the infant distance information detected by the distance detecting means is cross-referenced with the infant position information detected by the position detecting means, and the successive positions of each infant are detected while individually identifying each infant. (for example, Japanese Unexamined Patent Application Publication No. 2004-96501).
As another example, a motion sensor may be built into an image stabilization unit for an imaging apparatus as follows. The image stabilization unit is provided with: a wobble sensor that detects wobble; an imaging unit that includes an imaging element and optics; a chassis that supports the imaging unit; and an actuator. The actuator stabilizes the apparatus by proportionally driving the imaging unit and the chassis relative to the wobble detected by the wobble sensor. The chassis covers the imaging unit with at least a lateral part and a bottom part. The wobble sensor is disposed farther inward than the outer surface of the lateral part of the chassis part. (for example, Japanese Unexamined Patent Application Publication No. 2006-154345).
Also, as more and more devices become equipped with motion sensors, it is anticipated that motion user interfaces (motion UIs) will become common. Herein, a motion UI refers to a UI whereby a user can issue commands, input data, and perform various other actions with respect to a device by tilting and moving the device. Such a motion UI may be used instead of, or in conjunction with, other input methods such as a mouse, keyboard, or touch panel.
Operating a motion UI is easier than operating other input methods such as a mouse, keyboard, or touch panel. Consequently, motion UIs are attracting attention as a type of UI for operating devices easily.
Mobile phones equipped with motion UIs have been proposed. For example, a mobile phone may be provided with a gesture sensor such as a three-dimensional acceleration sensor. In so doing, particular gestures can be detected, such as the user shaking the mobile phone. The mobile phone controls the production of musical tones in accordance with the gestures detected by the gesture sensor, and the musical tones controlled according to the user gestures are emitted from a speaker. (for example, Japanese Unexamined Patent Application Publication No. 2003-76368.)